Images used in computer graphics are comprised of many small polygons of various shapes and sizes. The algorithm to sort a polygon using digital techniques is well known. However, it is generally performed in software on a microprocessor. For real time applications, that is, situations where the display must be updated 20 times a second or more, the current state of the art is too slow. This is due to the fact that prior art devices depend primarily on software techniques and do not incorporate a viable hardware approach.
The present invention overcomes the disadvantages of the prior art by implementing a polygon sort algorithm in electronic hardware, thereby allowing a much faster polygon sort speed. It also pipelines the polygon data so that a new polygon can be loaded into the hardware at the same time it is being sorted and simultaneously as a sorted polygon is being output to a graphics rendering engine. The invention also provides an apparatus which implements a polygon sort algorithm using a method wherein the polygon sort engine is never idle.